The present invention is generally related to hands free phone sets. Such a phone set does not require the user to pick up and hold the handset when the user is on the line. This means that the phone set does not restrict the freedom of the user as it leaves his hands free to be able to carry on with other work at the same time. Due to this benefit, such phones are becoming increasingly popular for use in the office and especially as car phones.
In the prior art, the ideal hands free phone set will be able to handle the necessary operations for making or finishing a call such as off-hook, dialling and on-hook by using voice recognition technology. However, this is still in the first stage of actual usage in the market because of its high cost, high power consumption and the complicated formalities to use it. Accordingly, in the usage of present phone sets, it is customary for the phone user to use the keypad on the phone to enable off-hook, dialling and on-hook by touching the particular keys. For instance, to control speaker volume, etc., it will be necessary to key a button on the phone set. This means that the user can still enjoy a hands-free conversation which will occupy most of the actual connection time. However, the user will need to directly operate the keypad at least twice for one call (off-hook and on-hook). In the case of dialling, more complicated formalities are necessary. Normally the user will need to touch the keypad more than ten times to make a call. This will sometimes cause wrong dialling even in normal use. To reduce such an inconvenience, it is becoming more common for phone sets to provide a memory for storing phone numbers. Therefore, instead of keying in the digits for the phone number, it will be necessary simply to key in the short dial number which can then be checked against the corresponding number shown on the display. Some useful improvements similar to the one mentioned above have been introduced, but not very satisfactorily in some cases. For instance, in the case of the car phones, it is very troublesome for a driver to push key buttons and then check the display when only able to glance quickly at the phone set. In addition to this, there is seldom adequate space to install the phone set suitably in the car, not only for the above-reason, but also for safety driving and equipment protection from severe environmental conditions such as strong sunlight irradiation, etc., harmonization with car fascia and also ensuring passenger room is not restricted.